Louisiana Legislature Passes 2% Renewable Fuels Standard
Michelin Survey on Sustainable Mobility

IFP Showing CNG Prius at Challenge Bibendum (updated)


IFP (Institut Français du Pétrole) is presenting a CNG-electric hybrid prototype vehicle based on the Toyota Prius at this Challenge Bibendum, running in Paris from 8-12 June 2006. IFP co-developed the CNG Prius with Gaz de France (GDF).

The use of CNG as a fuel for the engine drops the carbon dioxide emissions for the Prius below 80g/km, according to IFP—about half those of a conventional vehicle in that weight class (1,300 kg), and more than 20% below the standard Prius carbon dioxide emissions of 104 g/km.

The prototype is a single-fuel vehicle. The IFP-Gaz de France team replaced the original gasoline tank with a 22-liter natural gas tank made of composite materials. The engineers repaced the gasoline injectors with a manifold and natural gas injectors, and installed high- and low-pressure natural gas lines. A dedicated engine control system manages the injection time.

Gaz de France and IFP have worked together on other natural-gas-powered vehicles, including a Smart demonstrator developed in 2004, which featured a downsized engine and ran on natural gas alone. The collaborators are now developing a Smart natural gas hybrid prototype as well.

IFP also developed the natural-gas engine used in the CLEVER urban micro-car project. (Earlier post.)

The IFP-GDF prototype is the second CNG Prius prototype to appear at a major international event this year. In March two West Swiss natural gas companies—Holdigaz SA and Gaznat SA—displayed a stock Toyota Prius retrofit with a natural gas fuel system at the Geneva auto show. (Earlier post.)


John W.

Curious what this will do for the mileage.

John Baldwin

All vehicles should run on CNG and be hybrids. Its obvious, no technical issues.......great saving in CO2, great for air quality, great for energy eficiency. Germany has built 750 CNG stations in past 4 years, market now taking off big time. Range on CNG is not an issue as the vehicles get more fuel efficient so you need less...bye bye hydrogen!!


Did they increase compression ratio?

Roger Pham

Exactly! All vehicles should be hybrids and run on CNG or even LNG if longer range in a short period will be needed. The vehicle can have one 5000-psi tank insulated for both CNG and LNG. LNG is denser so vehicle can go farther, but even if all the liquid NG evaporated, the 5000psi pressure will still keep a lot of methane in the tank.
And why not Hydrogen too? Hydrogen, if produced using renewable energy sources, will be a lot more efficient than Methane synthesized from renewable energy sources such as solar or wind. That same 5000-psi insulated tank can be used for compressed H2 or LH2. You'll go only 1/3-1/2 as far with Hydrogen fuel on that same tank, but that will be sufficient for local commute, and may last for 3-5 days between fillup for commuting. For long trip or a lot of driving in one day, you will fill up your tank with CNG or LNG. Cars can be designed to use both H2 and Methane interchangeably using a fuel-type sensor, with direct high-pressure cylinder injection. Hydrogen and Methane can co-exist as our future energy currency. Bye bye fossil fuels!!!


And after you start using that natural gas for vehicles, you'll be paying $1500 a month to heat your house in the winter.

shaun mann

CNG does certainly have some advantages. It also has some problems, including:

1) a spotty distribution system,
2)low energy density (they didn't mention the range of the prius in the article, but it is likely to be less than the petrol version),
3)the cost and placement of a large high-pressure tank, 4)the danger of storing 25 gallons of a highly explosive highly pressurized gas inside a vehicle expected to be involved in high-energy collisions

and after all that, you're still using a fossil fuel, so why bother?

Sunny Tai

Back here in Australia, Melbourne, almost every petrol station has a LPG pump (Liquified Petrolium Gas, which i presume is LNG). The local manufacturers (holden and ford australia) and aftermaket supplies has sold cars with LPG tanks for years. Many fleet as well as private cars have this conversion. There doesn't seem to be any safety issues with this conversion. As far as I know, the only disadvantages i see are:

1) some systems eat into boot space, since the normal petrol tank is kept, so the vehicle is kind of a flex-fuel vehicle.
2) the LPG range is shorter
3) the engine produces slightly less power

Apart from that, an LPG conversion saves money (LPG cost half as much as petrol) and produces less emissions. A vehicle like this would be excellent for Australia, as we already have an established infrastructure.

Rafael Seidl

No manufacturer currently offers an LNG vehicle as the cost of placing a cryotank in a vehicle is fairly astronomical. Instead, CNG at 200 bar is typically used. Researchers are looking for ways to increase that to 300 bar and, to replace the heavy steel tanks with affordable composite alternatives. So far, regulators in Europe are not permitting designs in which the CNG tank becomes an integral part of the load-bearing structure.

All this limits the range of CNG vehicles. Moreover, the extra weight of the tanks in the rear of the vehicle reduces traction in front-wheel drive vehicles. CNG engines usually deliver about 10% less power than the base gasoline variant, because the fuel limits the amount of fresh charge that can be drawn in. One option would be to switch from port to direct injection. Another is super- or turbocharging.

Methane has a RON of ~120, permitting higher compression ratios to ~14 and/or advancing the ignition. Unfortunately, the distribution netowrks for CNG are not yet dense enough to permit monovalent (CNG-only) operation. Opel has gone further than most by offering monovalent-plus systems with a compression ration of 12.5 and a small emergency gasoline tank. In gasoline mode, however, the ignition has to be retarded to avoid engine knock, leading to poor fuel economy and performance.

CNG is not an appropriate motor fuel in all countries. Argentina and Italy currently have the most CNG vehicles. Much of Western Europe gets gas from Russia and, is looking for more from the Middle East by way of the proposed Nabucco pipeline, at which point vehicles would no longer compete with space heating for fuel. Australia has significant gas reserves, as do Canada, Bolivia, South Africa, Algeria etc. Iran is importing (!) gasoline from India instead of using its own vast gas reserves for transportation.

Unfortunately, many major markets, such as the US, Japan, China and India, have relatively few indigenous natural gas reserves. If they decide they need an alternative to oil to meet their transportation needs, a mix of renewable biofuels and synthetic Fischer-Tropsch liquids from coal or gas may be more appropriate. Another option is the local production of scrubbed biogas, for use in CNG vehicles.


Just goes to show to what lengths Big Oil will go to have consumers avoid plugging into the Grid. Go see "Who Killed the Electric Car?" when it opens.

Rafael Seidl

Note to EV enthusiasts -

Bob Lutz (GM Exec. VP of Product Development) was recently quoted in a BusinessWeek article that the company's greatest mistake was discontiniung the EV-1. They have the plans on a shelf somewhere. GM could earn a lot of goodwill if it showed contrition and simply re-introduced the model with an updated drivetrain.

So why don't they? Are they really just too proud to eat humble pie? If so, why has no other large manufacturer pre-announced a similar EV or even a PHEV vehicle, given current gas prices?

Could it be that the warranty risk is still too high or, that the market is still too limited in scale? After all, range and recharge time are always going to be problems with a pure EV.

My guess is that normally, the break-even point would probably lie somewhere between 500,000 and 1,000,000 units. Perhaps GM has already written off the R&D cost, in which case it might be lower.

Roger Pham

Reply from EV enthusiasts to Rafael,
"So why don't they?"
The evidences seem to have pointed toward simply a collusion between the Big 3's, Big Oil and Bush Adm to avoid CAFE mandate and other potentially costly emission regulations, in return for killing the petrol-sparing electric car/hybrid program while advancing the highly profitable SUV's with obvious consequence of high petrol consumption to satisfy Big Oil and Bush Administration. Japan and Europe simply aren't yet controlled by Big Oil. Let's hope that things remain that way.

Re: CNG usage
CNG can be a RENEWABLE FUEL AS WELL AS A FOSSIL FUEL. For now, even fossil-source CNG is still cheaper than gasoline. Let's set up infrastructure for CNG/H2 usage. When fossil source of CNG will be depleted, then we shall synthesize CNG (methane) and hydrogen from solar, wind, biomass sources and continue to use this fuel without any shift in the CNG/H2 infrastructure. CNG/H2 as renewable fuels will be a lot cheaper and quickly produced than Fischer/Trophs synthesis of liquid petroleum from coal or gasified biomass or hydrogen + CO2.

Cryogenic tank for LNG too expensive? BMW is working on LH2 automobiles for the masses, which requires a lot colder temp and a lot larger tank.

tom deplume

LPG and LNG are very different things. LNG is liquid methane for the most part. Methane needs temps far below zero to liquify. LPG is mostly propane and butane which can be liquified at room temp and low pressure.


Roger- it is the consumers in the USA vs those in Japan and Europe who are a problem not the companies. Japan is the 3rd heaviest consumer of petroleum (With about 40% the population of the US) due to a lack of natural energy sources but their companies responded to what the consumer wanted (smaller, more fuel efficient vehicles). Granted they do tax larger displacement engines. In the USA, until 2003 when gasoline prices started rising fast, the majority of consumers CHOSE to buy large, wasteful vehicles. If SUVs didn't sell so well in the 90s the USA automakers would not have continued to make larger and more powerful versions.

BMW may be working on LH2 but that doesn't mean it won't be expensive...hell universities have thoughts of producing cars with a structure made out of carbon nanotubes but that doesn't mean it won't take the entire GDP of the US to pay for such a thing (just because someone is working on something it doesn't amount to squat).

Roger Pham

Patrick-The montrous SUV's came about because of a lax CAFE standard that has failed to rise in the past several decades, AND a spurious CAFE loophole that classifies SUV's as trucks and thus exempts them from CAFE standard for cars, and exempts SUV's from more stringent emission standard for cars. THE CONSUMERS CANNOT BUY WHAT THE AUTOMAKERS DON'T MAKE!!!. The auto makers don't make vehicles that will be eventually outlawed by increasing tougher CAFE standard or emission standard. That's why I said there was a collusion between the government and the industry which bribes the government to set lax standards in the industry's favor, at the expense of the environment and at the expense of our country's future.

There can be no doubt that if the government has set gradually increasing standard for CAFE and for exhaust emission, that eventually gas-electric hybrids and eventually EV will have to be produced to satisfy that standard. Of course, the shortsighted industry will cry foul in the name of economic growth, but look at who is holding the short end of the sticks now? (The Big Three Autos) While Toyota and Honda are reaping huge profits after having invested billions of dollars to produce the highest possible MPG and the cleanest emission standard. The consumers responded with a long waiting list to buy the hybrids with the highest fuel economy, which also have the cleanest exhaust emission.

Patrick, tell me this: Why is our jobs are moving over seas, we can't control our border with further job loss from within our border, our health care expenses is increasing at three times the rates of inflation causing our industry going into a tail spin due escalating benefit cost, our industrial giants are faltering, our budget deficit and foreign trade deficit are unsustainable...etc...etc...? Especially when the US has invented most of the technologies that foreign producers are increasing dumping into our market. Are you blaming it on the consumers too? For buying too many imports and voting for lousy politicians? Just ask Duke Cunningham, or Tom Delay, Abramoff, or more names to come...Or is it because of a short-sighted collusion between the industry and the government for their own enrichment at the expense of the rest of the country? Where is patriotism? WHERE IS TRUE LEADERSHIP??? Who will protect our workers and our consumers with smart trade policy? Who will come up with smart renewable energy policy to spur our economic grow into that direction, creating more jobs and at the same time eliminating our foreign energy dependency, increase our national security, clean up our environment, and thrwart global warming? NOT WHEN BIG OIL IS IN CHARGE!!! They've got to sell trillions more of barrels of oil at cut-throat prices (thanks to the Bush Adm. and to our SUV drivers) before they will invest their ill-gotten gains into renewable energy.
BMW is no dummy. They don't waste their money on something the way GM's plowing theirs money and the taxpayer's money into freedom CAR program (Fuel cell)that will have little chance of near-term success. Methane and H2 powering hybrid electric-ICE cars is a much more realistic near-term project aiming at petroleum replacement, and a real BRIDGE between fossil fuel now and renewable fuel of the near future.


Do you really think GM or Ford would really create a monstrous SUV just because they can? No they make it because the consumers (at the time) wanted it. Stop making excuses for the lack of responsibility of consumers. Tell me, why doesn't Honda have a stable of 5000 and 6000lb SUVs? They sell vehicles in the US. Oh, here is where you will say the US companies were forced at gun point by "lax laws" to create wasteful vehicles?

If consumers stopped buying SUVs what do you think will happen? Do you think the carmakers will continue to build SUVs and people will be "forced" into buying them? Yeah right.

Why do our jobs move overseas? CEOs, stockholders and other rich folk want to save cost (current tax doctrine makes it easy for them) and see cheap labor elsewhere but guess what? Some of those call center jobs shipped off to India are starting to come back to the US and frankly consumers could voice their opinion with their dollars and choose to spend on only items manufactured in the US. I don't see it as being bad that we have labor intensive products manufactured elsewhere.

Here is an example: You want to buy your groceries from a place with a strong renewable resource program go to Whole Foods. You will get food from a company strongly environmental in the way they conduct business...but you'll pay a 100-200% premium on most goods from them. You could get goods manufactured in the US...but then you are amortizing the costs of Unionized labor (superficially high wages and benefits).

Harvey D.

Why is it that USA Big-3 can locally produce heavy (3500 - 4000 lbs) 7-passenger minvans gaz guzzlers (18-20 mpg) at a very competitive $15K price but can't produce a reliable, more efficient (50-55 mpg) lighter/smaller (2000 lbs) car for much less or around $10K?

If high labour cost is the main cause, why can Toyota and Honda USA do it and make good profits? Or, is the main reason that we don't want to drive smaller, more efficient vehicles and that cheap gas (less than half European price) make gas guzzlers affordable.

Smaller Hybrids with improved battery pack + lightweight clean diesel on-board genset would be an excellent interim solution to reduce oil consumption and GHG by 50+%. To further reduce fuel consumption and GHG, the on-board genset could be replaced, as an option, with a quick charge higher performance battery pack, when available at a lesser cost.

Lightweight gensets + improved batteries + electronic control systems + other components could be manufactured in China, India or other low labour cost countries to reduce cost. Local USA/Canada high labour cost factories could do limited final assembly ONLY unless they can compete.

All the technology required is here. What's stopping the Big-3? Our accquired love for heavy SUV gas guzzlers? If so, that could be changed fast enough with a progressive carbon tax to double the price of gas, slaes tax and registration fees over a 10-year period.

Rafael Seidl

Harvey D. -

a long time ago, GM, Ford and Chrysler agreed to pay for the health care and pensions of its retirees. By now, these obligations have mushroomed into huge liabilities. Toyota and Honda retirees rely on regular MediCare and Social Security. So be careful when you point fingers, these companies really do not have similar payroll structures right now.

Roger Pham

Patrick said: "Stop making excuses for the consumers..."

Consumers as a whole are not well informed, and tend to follow their basal instincts to make decisions. Government with expert advisors is better informed and should make public campaign to help motivate and to inform the public to make the right decision. We have made tremendous progress in the fight for heart diseases, stop smoking, seatbelt usage, clean air, lead contamination, cancer prevention etc...thru public campaign and appropriate laws to nudge the public in a safe direction. Government should lead and not be lead by powerful interest groups who have nothing but their selfish self-interest at the expense of our national future, our children and our global environment.

Free trade should be fair, and not with countries with unfair advantages. There can be no free trade with countries with so lax environmental and worker safety laws, because, in so doing, we will be undoing our own hard-won standard, AND encourage them to poison themselves and our global environment in so doing. The pollution problem in China and many other countries is not sustainable, and the pollution are coming to our shores.


"Do you really think GM or Ford would really create a monstrous SUV just because they can?"

GM alone spend $3 billion a year in advertising just to move what people "want"? Yeah right.

"High and Mighty: SUVs: The World's Most Dangerous Vehicles and How They Got That Way"


I sure wish I could get my 2004 Toyota Prius Hybrid converted to run on CNG, Compressed Natural Gas. I'm actually looking for someone here in America to do this conversion for me. if you know anyone please write me their information at eyesee@sbcglobal.net. Thank you much!


I own a cng/gasoline bifuel car, I love it...I get 33 miles to the gallon and I lose absolutely no performance, as a matter of fact I believe the 130 octane level of the cng gives me better performance. As for the fuel tanks, I worked at a Chrysler dealership and i have seen the cheap flimsy gasoline tanks come in punctured or broken...most gasoline tanks nowadays are made of plastic and as we all know gasoline tanks can and do burst during a collision...remember the "Pinto" explosions? I drive with no fear of a cng tank explosion, these tanks are very heavy metal and i read a government study before I bought my bifuel car and in this article the government found the cng tanks to be way safer than a regular gas tank. It is estimated that an engine that has been operated on cng will last twice as long as a regular gas engine and the oil only hasta be changed every 15,000 miles compared to 3000 miles for a gas engine, thus saving more oil. And the tax credits for owning a cng car are great and you can buy a cng home fueling station for your house which also carries great tax credits. The only downside I have found is the availability of cng, I live near Tulsa and there are only a few places that sell cng but when I compare the 90 cents a gallon I pay for cng to the 3 dollars a gallon (and sure to go higher) for gasoline I can put up with a little inconvenience.


Do NOT believe a thing these supporters of big 3 USA automakers are saying !! GM, Ford & Dodge all STOPPED their cng vehicles during Bush Admin at same time that EPA ramped up tryanical "certification" rules that virtually prevent vehicles from being converted to cng!! Toyota stopped selling terrific cng Camry after 2001 . . . why, Big Oil lobby money!!!

Big Oil, Pres Bush & US automakers ARE DEFINITELY preventing spread of cng here in USA!!! It's TRUE!! No need to read tea leaves, just look around!!

I bought 2 terrific bi-fuel Chevy Cavaliers that State of Georgia was selling from fleet at $7,000 to $8,000 with less than 40k miles ; I get 30 mpg on cng that only costs $0.91 per gge (gallon of gas equivalent) here in Oklahoma. Show me any kind of gasoline vehicle for $8,000 that gets equivalent of 100 mpg since cng is $0.91 while gasoline is $3.00 - - in Utah, it's better yet at $0.64 for cng and state gives you $3,000 tax credit for buying a cng vehicle !!! Sadly, even here in OK very few people know about cng. The reason, automakers don't promote it, instead cable TV, print ads, etc. are full of Hummer ads, Impala SS, etc. with no concern for economy or emissions!!

CNG is DEFINITELY the answer the USA needs now for TRANSPORTATION REVOLUTION !!! Vote the scheister Pres Bush out, disband the EPA, and let's start over!! Every large vehicle sold in USA should be bi-fuel with cng & gasoline (along with E85 capable). Automakers like GM, Ford, VW, Mercedes, etc. need FORCED to sell cng vehicles in USA that they ALREADY SELL in Europe and Asia!!! Every city should have it's own public cng refueling site, towns along major highways should have public cng refueling, all landfills should have biomethane plants to capture cng that trash trucks could use for fuel, wastewater plants should capture biomethane so that city vehicles could run on cng, etc. so that cng actually could grow in USA. It can be done . . other countries all around the world are doing it!! USA can too!!

Educate yourself . . see:

Sincerely . . . avig CNG supporter,


The comments to this entry are closed.